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HEAT FAN‐OFF TIME IN SECONDS
To adjust fan-off timing, reposition jumper across pins to
achieve desired setting.
NO JUMPER
60
90
120
180
60
90
120
180
60
90
120
180
60
90
120
180
60 Second 
off Time
90 Second 
off Time
120 Second 
off Time
180 Second 
off Time
Figure 32   
Constant Torque Motor
EL180UHE units are equipped with a constant torque ECM 
motor. It has a DC motor coupled to an electronic control 
module both contained in the same motor housing. The 
motor is programmed to provide constant torque at each of 
the ve selectable speeds. The motor has ve speed taps. 
Each tap requires 24 volts to energize.
Input Voltage Requirements
The circuit is designed to be operated with AC voltage. A 
voltage of 12 to 33VAC is required to energize the motor. 
Expected current draw will be less than 20mA.
Blower Speeds
Follow the steps below to change the blower speeds.
1 -   Turn off electrical power to furnace.
2 -   Remove blower access panel.
3 -   Disconnect existing speed tap at integrated control 
speed terminal.
NOTE - Termination of any unused motor leads must be 
insulated.
4 -   Place unused blower speed tap on integrated 
control “PARK” terminal or insulate.
5 -   Refer to blower speed selection chart on unit wiring 
diagram for desired heating or cooling speed. 
See  Product  Specications  manual  for  blower 
performance data.
6 -    Connect selected speed tap at integrated control 
speed terminal.
7 -   Resecure blower access panel.
8 -   Turn on electrical power to furnace.
9 -   Recheck temperature rise.
Electronic Ignition
The integrated control has an added feature of an internal 
Watchguard control. The feature serves as an automatic 
reset device for integrated control lockout caused by igni-
tion failure. This type of lockout is usually due to logas line 
pressure. After one hour of continuous thermostat demand 
for heat, the Watchguard will re-set and remake thermostat 
demand to the furnace and automatically reset the integrat-
ed control to begin the ignition sequence.
Service
 WARNING
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
Failure to follow safety warnings exactly 
could result in dangerous operation, serious 
injury, death or property damage.
Improper servicing could result in 
dangerous operation, serious injury, death, 
or property damage. Before servicing, 
disconnect all electrical power to furnace.
When servicing controls, label all wires prior 
to disconnecting.
Take care to reconnect wires correctly.
Verify proper operation after servicing.
 WARNING
The blower door must be securely in place when the 
blower and burners are operating. Gas fumes, which 
could contain carbon monoxide, can be drawn into the 
living space resulting in personal injury or death.
Annual Furnace Maintenance
At the beginning of each heating season, and to comply 
with the Lennox Limited Warranty, your system should be 
checked by a licensed professional technician (or equiva-
lent) as follows:
1 -   Check wiring for loose connections, voltage at 
indoor unit and amperage of indoor motor.
2 -   Check the condition of the belt and shaft bearings 
if applicable.
3 -   Inspect all gas pipe and connections for leaks.
4 -   Check  the  cleanliness  of  lters  and  change  if 
necessary (monthly).
5 -   Check the condition and cleanliness of burners and 
heat exchanger and clean if necessary.
6 -    Check the cleanliness of blower assembly and 
clean the housing, blower wheel and blower motor 
if necessary . The blower motors are prelubricated 
for extended bearing life. No further lubrication is 
needed.
7 -    IInspect the combustion air inducer and clean if 
necessary.
8 -   Evaluate the heat exchanger integrity by inspecting 
the heat exchanger per the AHRI heat exchanger 
inspection procedure. This procedure can be 
viewed at www.ahrinet.org